JP2023136977A - Capacitor and power conversion device - Google Patents

Abstract

To reduce the number of components in a power conversion device that requires a ferrite core to reduce manufacturing costs and improve ease of assembly.SOLUTION: A capacitor 1 includes a hollow circular capacitor body 10. A hollow circular ferrite core 3 is provided in a hollow portion 14 of the capacitor body 10 coaxially with the capacitor body 10. The capacitor body 10 includes terminal portions 13P and 13N for P and N poles connected to a semiconductor module 4. The terminal portions 13P and 13N are exposed from the surface of the capacitor body 10 near the hollow portion 14 and protrude toward the axis of the capacitor body 10.SELECTED DRAWING: Figure 1

Description

The present invention relates to the structure of a capacitor.

A power converter device, exemplified by an inverter device for a vehicle, includes a switching element such as an IGBT (insulated gate bipolar transistor). The inverter device needs to include a ferrite core in order to cut external noise and noise generated from the switching elements. The ferrite core is attached to, for example, a bus bar connected to terminal portions for P and N poles that are input portions of DC power from a battery of the inverter device. Patent Document 1 is known as a prior art for attaching a ferrite core to a bus bar of an inverter device.

JP2016-98678A Japanese Patent Application Publication No. 2004-119874 Japanese Patent Application Publication No. 2013-197486

Since the ferrite core and other parts of the power conversion device, such as the capacitors in Patent Documents 2 and 3, exist as independent components, it is necessary to attach the ferrite core to the bus bar in consideration of the space for placing various parts of the power conversion device. There is.

On the other hand, the capacitors disclosed in Patent Documents 2 and 3 have a special shape including a hollow portion.

In view of the above circumstances, it is an object of the present invention to reduce the number of parts of a power conversion device that requires a ferrite core, thereby reducing manufacturing costs and improving ease of assembly.

Accordingly, one aspect of the present invention is a capacitor that has a hollow circular capacitor main body, and a hollow circular ferrite core is provided in the hollow portion of the capacitor main body coaxially with the capacitor main body.

In one aspect of the present invention, in the capacitor, the capacitor main body portion includes terminal portions for P and N poles connected to electrical components, and the terminal portions for P and N poles are connected to the It is exposed from the surface near the hollow part of the capacitor body and protrudes toward the axis of the capacitor body.

In one aspect of the present invention, in the capacitor, the electrical component is a semiconductor module of a three-phase power converter, and the P-pole and N-pole terminal portions are located at the periphery of a hollow portion of the capacitor body. Three lines are arranged along the line corresponding to the three phases.

In one aspect of the present invention, in the capacitor, a bus bar connected to the electric component and the P-pole and N-pole terminal portions is inserted through the ferrite core.

In one aspect of the present invention, in the capacitor, a cooler is disposed between the capacitor main body and the electrical component.

One embodiment of the present invention is a power conversion device including the above capacitor.

According to the present invention described above, it is possible to reduce the number of parts of a power conversion device that requires a ferrite core, thereby reducing manufacturing costs and improving ease of assembly.

(a) A perspective view of a capacitor that is one embodiment of the present invention, (b) a plan view of the capacitor, and (c) a side view of the capacitor. (a) A perspective view of a capacitor that is one embodiment of the present invention in which semiconductor joules are arranged, (b) a plan view of the capacitor, and (c) a side view of the capacitor. (a) A plan view of a capacitor that is an embodiment of the present invention in which a cooler is arranged, and (b) a side view of the capacitor. A circuit diagram of an on-vehicle inverter device.

Embodiments of the present invention will be described below with reference to the drawings.

A capacitor 1, which is an embodiment of the present invention shown in FIG. 1, is applied to a vehicle-mounted three-phase inverter device 2, which is one embodiment of a power converter device shown in FIG. 4, for example.

The capacitor 1 has a hollow circular capacitor main body 10 . A hollow circular ferrite core 3 is provided in the hollow portion 14 of the capacitor body 10 coaxially with the capacitor body 10 .

The capacitor main body 10 has a hollow cylindrical resin case 11 that accommodates a capacitor element (not shown), and a potting part 12 in which the resin case 11 is filled with a sealing resin. The potting section 12 includes a pair of terminal sections 13P and 13N for P and N poles connected to the capacitor element. The terminal portions 13P and 13N are exposed from the surface near the periphery of the hollow portion of the capacitor body 10 and protrude toward the axis of the capacitor body 10.

Three terminal portions 13P and 13N are arranged along the periphery of the hollow portion of capacitor main body portion 10, corresponding to the three phases (U phase, V phase, and W phase) of inverter device 2. As shown in FIG. 2, power cards corresponding to the U-phase, V-phase, and W-phase of the inverter device 2 as electrical components of the inverter device 2 are connected to the terminal portions 13P and 13N of the U-phase, V-phase, and W-phase, respectively. type semiconductor modules 4U, 4V, and 4W are connected.

As shown in FIG. 4, the semiconductor modules 4U, 4V, and 4W are equipped with an upper arm 41 and a lower arm 42 made of IGBTs. The collector terminal 4P of the upper arm 41, which is the P-pole terminal of the semiconductor modules 4U, 4V, and 4W, is connected to the P-pole terminal portion 13P of the capacitor 1, as shown in FIG. Similarly, the emitter terminal 4N of the lower arm, which is the N-pole terminal of the semiconductor modules 4U, 4V, and 4W, is connected to the N-pole terminal portion 13N of the capacitor 1.

Further, an input bus bar P inserted into the hollow part of the ferrite core 3 is fastened to the collector terminal 4P and the terminal part 13P of the semiconductor module 4U by a fastener. Similarly, an input bus bar N inserted through the hollow portion 30 of the ferrite core 3 is fastened to the emitter terminal 4N and the terminal portion 13N of the semiconductor module 4U by a fastener. Note that a discharge resistor 7 is connected to the input bus bars P and N.

Three P-pole terminal portions 13P of the capacitor 1 corresponding to the semiconductor modules 4U, 4V, and 4W are electrically connected by capacitor elements within the resin case 11. Similarly, the three N-pole terminal portions 13N of the capacitor 1 are also electrically connected by the capacitor element. Therefore, when the input bus bars P and N are connected to the collector terminal 4P and emitter terminal 4N of any one of the semiconductor modules 4, the power from the battery is also applied to the other two semiconductor modules 4. .

Output bus bars 5U, 5V, and 5W connected to the three-phase motor 5 in FIG. 4 are connected to the output terminals 43 of the semiconductor modules 4U, 4V, and 4W, respectively. Furthermore, a Hall current detector 6 is attached to each of the output bus bars 5U, 5V, and 5W.

According to the capacitor 1 described above, since the ferrite core 3 is coaxially and integrally provided with the capacitor 1 in the hollow part 14 of the capacitor 1, the ferrite core 3 can be installed without considering the space for ferrite core 3 in the inverter device 2. The ferrite core 3 can be attached to the input bus bars P and N. Therefore, the number of parts of the inverter device 2 that requires the ferrite core 3 can be reduced, so that manufacturing costs can be reduced and assembly efficiency can be improved.

In particular, since the terminal portions 13P and 13N are exposed from the surface near the hollow portion of the capacitor body 10 and protrude toward the axis of the capacitor body 10, the input bus bar P inserted into the ferrite core 3, The distance between N, capacitor 1, and semiconductor modules 4U, 4V, and 4W becomes shorter. Therefore, it is possible to electrically connect the input bus bars P, N to the capacitor 1 and the semiconductor modules 4U, 4V, 4W in a space-saving manner, and the length of the input bus bars P, N and the size of the inverter device 2 can be reduced.

Further, a plurality of terminal portions 13P and 13N can be arranged along the periphery of the hollow portion of the capacitor main body portion 10 depending on the number of semiconductor modules 4 of a single-phase or three-phase power conversion device. Therefore, the capacitor 1 of this embodiment can be applied not only to the three-phase inverter device 2 of FIG. 2 but also to a power conversion device including a DC capacitor, for example, a single semiconductor module 4 of a single-phase inverter device. Furthermore, the capacitor 1 is not limited to the above-mentioned power card type, but can also be applied to semiconductor modules of other specifications.

Further, when the input bus bars P and N are inserted through the ferrite core 3, they can be connected to the collector terminals 4P and emitter terminals 4N of the semiconductor modules 4U, 4V, and 4W, and the terminal portions 13P and 13N of the capacitor body 10. Therefore, the workability of connecting the input bus bars P, N, the semiconductor modules 4U, 4V, 4W, and the capacitor 1 is improved.

Incidentally, as shown in FIG. 3, a cooler 8 consisting of a heat sink for cooling the semiconductor modules 4U, 4V, 4W may be disposed between the capacitor main body 10 and the semiconductor modules 4U, 4V, 4W. Refrigerant is circulated and supplied to the cooler 8 via pipes 81 and 82. According to this aspect, not only the semiconductor modules 4U, 4V, 4W but also the upper surface of the capacitor 1 can be cooled, so that it is possible to improve the reliability of the power conversion device including the capacitor 1 and the semiconductor modules 4U, 4V, 4W. can.

DESCRIPTION OF SYMBOLS 1... Capacitor, 10... Capacitor body part, 11... Resin case, 12... Potting part, 13P... Terminal part for P pole, 13N... Terminal part for N pole, 14... Hollow part 2... Inverter device,
3... Ferrite core, 30... Hollow part 4, 4U, 4V, 4W... Semiconductor module, 41... Upper arm, 42... Lower arm, 4P... Collector terminal, 4N... Emitter terminal 5... Motor, 5U, 5V, 5W... Output Bus bar 6...Hall current detector 7...Discharge resistor 8...Cooler, 81, 82...Piping P, N...Input bus bar

Claims (6)

It has a hollow circular capacitor body,
A capacitor characterized in that a hollow circular ferrite core is provided in a hollow portion of the capacitor body coaxially with the capacitor body. The capacitor main body includes terminals for P and N poles connected to electrical components,
2. The terminal portions for the P and N poles are exposed from the surface near the hollow portion of the capacitor body and protrude toward the axis of the capacitor body. Capacitors listed. The electrical component is a semiconductor module of a three-phase power conversion device,
3. The capacitor according to claim 2, wherein three terminal portions for the P-pole and the N-pole are arranged along the periphery of the hollow portion of the capacitor body corresponding to the three phases. 4. The capacitor according to claim 2, wherein a bus bar connected to the electrical component and the P-pole and N-pole terminals is inserted through the ferrite core. 5. The capacitor according to claim 2, wherein a cooler is disposed between the capacitor body and the electrical component. A power conversion device comprising the capacitor according to any one of claims 1 to 5.

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